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Re: in which we present an ugly hack to make sys/queue.h CIRCLEQ work

> (I think that) strict aliasing rules implies that if two types
> "type{1,2}" do not match any of the aliasing rules (e.g. type1 is of
> the same type as the first member of type2, or type1 is a char, or
> ...), then any two pointers ptr{1,2} on type{1,2} respectively _ARE_
> different, because *ptr1 != *ptr2 per the aliasing rules and this
> implies ptr1 != ptr2.

Only if you actually evaluate *ptr1 and *ptr2 (in some cases, I think,
just one of them is enough).  Otherwise you're not accessing the
relevant object(s); the rule is about accesses to values, not about
pointers that, if followed, would perform certain accesses to values.

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